Mining-drill



' (No Model.) a v M. WOLFE 81s M. DEVLIN.

MINING DRILL.

No. 561,250. Patented June 2, 1896.

Int/anions:

UN TED STATES PATENT ()FFICE.

MARCUS WOLFE AND MICHAEL DEVLIN, OF ST. CLAIR, PENNSYLVANIA.

MINING-DRILL.

SPECIFICATION forming part of Letters Patent No. 561 ,250, dated June 2,1896. Application filed February 14, 1896. Serial No. 579,326. (Nomodeh) to the accompanying drawings, and to the let-.

ters of reference marked thereon, which form a part of thisspecification.

The invention relates to rock and coal drills, which are generallyprovided with a threaded bar having a crank on one end, a drill-bitsocket on the other, and a threaded socket set in a clevis between thebars, so as to make what is known among miners as a first-motionmachine. These drills have a N 0. 1O thread and cut one-tenth of an inchat each revolution; but they are liable to get out of order veryfrequently and produce much annoyance.

The special object of our invention is to make a more durable drill anda much more serviceable one by making the drill-bar to revolve in thefeed-barrel, so that it will be independent of the feed.

Figure 1 of the drawings is a perspective View showing all the parts ofdrill except the bit, and Fig. 2 a cross-section thereof.

In the drawings, A represents the holder, to which the drill may beattached at either end, and which has near said ends the collars a a,made fast 'thereto.- Between these collars is arranged the barrel B, inwhich the drill-bar rotates, while the said barrel remains stationary.The barrel B has an exterior thread I), which works in a guide-nut O,that has on opposite sides the studs 0 c, which screw into it throughthe ends of yoke D, the latter having a shank d to be secured in such aposition as to support the drill as may be required. The barrel B haspreferably at each end a ratchet-disk E, in which works the spring-pawlf on the lever F, the latter having an end ring f, which turns on thecollar a. The drill-bar may be turned by the crank G without being fedforward, while the barrel is turned to give the feed by the pawl, lever,and ratchet.

Our drill is fed to the rock or coal by the hollow screw, while it isforced into the coal or rock by rotating the drill-bar within thefeed-screw until the upper collar of the bar strikes the upperratchet-disk on the feedscrew, when the latter is again fed down on thebar. This is continued until the upper ratchet-wheel strikes the nut.Thus it will be seen that the feed-screw and drill-bar are operatedindependently of each other and by different means. i

What we claim as new is A reversible coal or rock drill having a collarand bit-holder at each end of the drillbar, and a feed-screw providedwith a ratchet, pawl, and lever at eachend as shown and described.

In testimony whereof we affix our signatures in presence of twowitnesses.

MARCUS WOLFE. MICHAEL DEVLIN. 'Witnesses THos. O. OooKILL, JNo. A.HAERTTER.

